Marketo doesn't have that feature built in natively, but it has multiple partners that specialize in all this with Marketo integrations. There are also external companies that don't integrate but also do it well, with prices ranging anywhere from free to 6 figures annually depending on the features you select.

also used both. Like everyone else is saying, both are great, but I found Litmus to be a little easier to use and share with others for review. It's a little more premium, but yeah... Definitely not going to break a corporate budget in most cases.

Exactly. At this point, email testing and deliverability testing has become so commoditized it's really all up to you in terms of what UX and secondary feature sets you prefer and how much you're willing to pay for them.

For those of you using EOA, could you provide a high level summary of how you use it in your Marketo email workflow? Do you just use it for testing email client rendering after you have created an email or are there other aspects you use? If you use their email templates, do you bring those into Marketo? Or maybe you do everything in EOA - design & test in their builder and bring the final code into Marketo?

If you are using templates for your emails, you really only need to test with EOA when developing the overall template and not email by email, as really you are only adding content to the pre set zone (but that decision is up to your organisation). If you are going to custom an email (Email 1.0), then the handiest solution is to copy and paste the custom code (raw HTML) and in EOA test it the via Email Testing on the left side menu, that way you don't have to send a sample to EOA and you can do things quicker, assuming you have the required Marketo email classes already.

In EOA look for:

Email 2.0 will be a bit different as it has a lot of Marketo's own syntax, so copying the raw code will throw up a lot of errors, so in this case, you'll have to have the code in Marketo and send a sample as normal to your EOA Auto-process Address. Again if your email is templated, you should only have to do this in the development stage. I suggest you utilize Modules more in Email 2.0 and test an email with multiple variations using that, then go towards a more 1 email template design rather than multiple templates that have different designs (Modules is the trick on how to do this).